1. Field of the Disclosure
The features herein relate to an inkjet head which ejects ink.
2. Description of the Related Art
In an inkjet head, having an ejection port which ejects ink and an ink flow path which supplies ink to the ejection port, ink ejection characteristics may be changed depending on an ink temperature.
Meanwhile, a performance of re-filling ink to the ejection port in the ink flow path may be changed depending on the ink temperature after ink ejection. For example, when the ink temperature increases, the ink easily flows, and hence, the ink is easily re-filled. In contrast, when the ink temperature decreases, the ink slowly flows, and hence, the ink is slowly re-filled. The change in ink ejection characteristics may be caused by the change in such performance of re-filling the ink.
For example, if the ink flow path is designed such that the ink is re-filled by a suitable amount when the ink temperature is high, the ink amount to be re-filled at a low ink temperature becomes insufficient. Thus, the ink ejection amount from the ejection port may become insufficient. In contrast, if the ink flow path is designed such that the ink is re-filled by the suitable amount when the ink temperature is low, the ink amount to be re-filled at a high ink temperature becomes excessive. Thus, the ink ejection amount from the ejection port may become excessive.
An inkjet head which adjusts ink ejection characteristics by deforming an ink flow path in accordance with an ink temperature is known. However, in the inkjet head, the ink flow path is deformed by using thermal expansion of the wall portion. In this case, the appearance of the deformation of the wall portion depending on the change in ink temperature is determined by the material, shape, and supporting method of the wall portion. Thus, it is difficult to adjust the wall portion to be deformed appropriately in accordance with the change in temperature.